Method of making strip



May 13, 1958 J. E. SILVASY ETAL METHOD 'OF` MAKING STRIP Original Filed June 50, 1951 2 Sheets-Sheal INVENTORS .TOHN E'. S/L VASY May 13, 1958 J. E'. slLvAsY Erm.

METHOD 0F MAKING STRIP original Filed June 3o, 1951 2 Sheets-Sheet 2 s, i fifi H I j.

INVENTORS 10H/v E s/L VA s y i 0a/s 7:4 more BY E/cHEg WA TTS, EcSE/ero/vs/v-Wf/VA/y Tfys METHOD or MAKING STRIP John E. Silvasy and Louis Taylor, Youngstown, Ohio;

' said Taylor assignortosaid Silvasy `Origina1 application June 30, 1951, Serial No. 234,524,

s claims. (c1. 754214) This invention relates to the art of making continuous sheet and strip from metallic powder and more specifically to improvements in rolling mills employed in the initial treatment of the powder.

This application is a division of our co-pending application, Ser. No. 234,524, filed June 30, 1951, now Patent No. 2,771,637, issued November 27, 1956.

The primary object of the invention resides in the provision of mechanism for intensifying the density of the powdered metal fed to the pressure rolls in a rolling mill, the preferred embodiment thereof comprising a pair of spaced shoes or friction plates arranged to oppose the propulsive effort of the powder feed mechanism and the translation of the compressed powder through the rolls.

Another object of the invention is to provide a combined guideway and friction plate assembly in a rolling mill for increasing the density of the powdered metal before ejection thereof from the rolls.

Another object of the invention is to provide mechanism in the rolling mill for varying the compressive effort of the friction plates upon the compressed powder.

Another object of the invention is to provide mechanism for adjusting the driving torque of the powder feed device compensative of the adjustment of the friction plates.

Further objectsof the invention reside' in the provision of a discharge control member in a rolling mill which is efficient of operation, economic of manufacture, durable of structure, and operable in the hands of unskilled labor.

Other objects and advantages, more or less ancillary to the foregoing, and the manner in which all the various objects are realized will appear in the following description, which, considered in connection with the accompanying drawings, sets forth the preferred embodiment of the invention.

Referring to the drawings:

Fig. l is a longitudinal sectional view of a continuous powdered metal strip unit including a rolling mill embodying the present invention;

Fig. 2 is a transverse sectional view through a portion of the mill, the section being taken on a plane indicated by the line 2 2 in Fig. l;

Fig. 3 is an enlarged sectional view through the powder feed conduit, pressure rolls, and the compression shoes or friction plates illustrated in Fig. l;

Fig. 4 is an enlarged sectional view of a fragmentary portion of the rolls and conduit; and

Fig, 5 is a lateral sectional view thereof, the section being taken on a plane indicated by the line 5 5 in Fig. 4.

Referring first to Fig. l, the strip or sheet mill comprises a motor having an adjustable torque coupling 11 mounted thereon, a conveyor screw 12 driven thereby, a housing 13 therefor, and a hopper 14 communicating therewith for the reception of powdered iron or other finely divided metal. The housing 13 is formed with a flange 15 on the outer end thereof which is connected arent with a companion'r flange on a feed conduit 16 having an outwardly ared end terminating in a narrow rectangular opening disposed in aligned relation with a passageway between a pair of spaced horizontal pressure rolls 17'. The end of the conduit 16 is designed to prevent the powdered iron from wedging at the throat of the rolls andthe upper and lower edges thereof are rounded to the contour of the rolls 17 for intimate engagement with the contiguous faces thereof. The side walls of the conduit protrude inwardly terminating at the center of' the vertical axes of the rolls in order to effect the even distribution of the powdered metal and delimit the width of the compressed powder strip. The rolls are mounted in the'customary manner in a frame 18, the passageway between the rolls being determined by adjustment of a screw 19 engaged in the usual manner' with the bearing blocks that house the journals for the rollers 17.

The rolling mill is provided with a pair of spaced, hardened steell shoes or friction plates 20 disposed in contiguous relation with the discharge end of the rolls 17. The lower plate 20 is arranged in tangential relation with the lower roll 17, the upper plate 20 being mounted for vertical adjustment in a housing 21 mounted on the frame 18 of the rolling mill through bolts 22. The upper friction plate is urged toward the lower plate by a spring 23 controlled by a screw 24 mounted in a bracket 25 connected to the frame 18 of the mill. The housing 21 for the friction plates 20 is formed with opposed ribs or flanges 26 on the lineal edges thereof which are disposed in aligned relation with the side walls of the conduit 16 to guide the compressed powdered metal ejected by the rolls 17. l

The mill is further provided with an endless conveyor belt assembly 27 adjacent the discharge end of the friction plates 20 and a sintering furnace 28 is mounted in aligned relation with the outer end of the conveyor belt assembly. The sintering furnace is of conventional form save that a trough or guideway 29 is mounted therein for the reception of the compressed powdered metal strip driven therethrough. A second mill supporting a pair of rolls 30 similar to the rolls 17 is mounted ad-v jacent the delivery end of the sintering furnace 28, and a reel 31 adjacent the outer end of the second mill is provided to receive the compressed and sintered metallic strip ejected by the rolls 30. The rolls 17 and 30 are rotated in the customary manner through gearing, not shown, from a suitable source of power.

In operation, the powdered metal is fed from the hopper 14 through the conduit 16 by the conveyor screw 12, the powdered metal being forced between the rolls 17 in a layer of constant width and depth. As the compressed powder is passing through the pressure rolls 17, the density thereof is further increased by the retarding action of the friction plates 20 which are set to oppose the propulsive effect of the screw 12 and tractive effort of the rolls 17. The load imposed upon the spring 23 may be regulated compensative of the tractive effort of the pressure rolls 17, which increases with the diameter thereof, and the torque adjustment of the powder feed mechanism illustrated herein as the conveyor screw 12.

During the initial run of the roll mill a plate of metal of requisite thickness is inserted between the friction plates 20 in order to initiate a back pressure on the powdered metal in the throat of the conduit 16. As the powdered strip passes through the rolls, the plate is dislodged and may be lifted from the conveyor before the end of the strip enters the sintering furnace.

The second rolling mill receives the compressed strip of powdered metal as it leaves the sintering furnace, the rolls 30 further compressing and working the heated 3, metal strip to the desired gauge. A hood or jacket 32 is provided between the furnace and adjacent mill to prevent undue heat loss in the metallic strip before it passes through the rolls 30.

Although the foregoing description is necessarily of a detailed character, in order that the invention may be completely set forth, it is to be understood that the specic terminology is not intended to be restrictive or conning, and that various rearrangements of parts and modifications of detail may be resorted to without departing from the scope or spirit of the invention as herein claimed.

We claim:

1. The method of producing sheet metal strips from powdered metal comprising feeding powdered metal under pressure to pressure rolls, compressing the powdered metal by rolling in said rolls, frictionally resisting the passage of the material from the rolls to increase the compression of the material between the rolls, sintering the material after the same has been compressed, and then finish-rolling the strip.l

2. The method of producing sheet metal strips from powdered metal comprising feeding powdered metal under pressure between pressure rolls, applying cornpressive effort and frictional resistance to the material as it leaves the pressure rolls, sintering the material after the samek is compressed, then finish-rolling the material after the sintering operation.

3. The method of producing sheet metal strips from powdered metal comprising feeding powdered metal 4 under pressure to pressure rolls, compressing the powdered metal by rolling in said rolls, and frictionally resisting the passage of the material from the rolls to increase the compression of the material between the rolls.

4. The method of producingsheet metal strips from powdered metal comprising feeding powdered metal under pressure between pressure rolls, and applying compressive effort and frictional resistance to the material as it leaves the pressure rolls.

5. The method of producing sheet metal strips from powdered metal comprising feeding powdered metal to pressure rolls, applying pressure in said powdered metal toward said rolls, `further compressing the powdered metal by rolling in said rolls, and frictionally resisting the passage of the material from the rolls to produce a pressure in the material toward said rolls.

References Cited in the file of this patent 

1. THE METHOD OF PRODUCING SHEET METAL STRIPS FROM POWDERED METAL COMPRISING FEEDING POWDERED METAL UNDER PRESSURE TO PRESSURE ROLLS, COMPRESSING THE POWDERED METAL BY ROLLING IN SAID ROLLS, FRICTIONALLY RESISTING THE PASSAGE OF THE MATERIAL FROM THE ROLLS TO INCREASE THE COMPRESSION OF THE MATERIAL BETWEEN THE ROLLS, SINTERING THE MATERIAL AFTER THE SAME HAS BEEN COMPRESSED, AND THEN FINISH-ROLLING THE STRIP. 